A technique for a vehicle to detect an obstacle approaching the surroundings of the vehicle by using an obstacle sensor mounted on the vehicle has heretofore been known. For example, in Japanese Patent Application Publication No. 2009-280109, in order to detect a slight shock or a burglary and record it as a video image when a vehicle is parked or stopped, shooting of an obstacle by an on-vehicle camera and recording of its video image are started in response to detection of the obstacle by an ultrasonic sensor.